KR101792907B1 - Power Allocation and Parameter Selection Method for MIMO OFDM Block AMC and System thereof - Google Patents

Abstract

A method and system for determining transmission power allocation and parameters in a MIMO-OFDM based block AMC environment are presented. In a MIMO-OFDM based block AMC environment, a transmission power allocation and a parameter determination method include estimating a channel state at a receiver through data received from a transmitter through wireless communication; Transmitting the channel information obtained by estimating the channel state at the receiving end to the transmitting end via the wireless communication through feedback; Determining parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment using the channel information at the transmitter; Generating the next transmission data using the parameters at the transmitting end; And transmitting the data from the transmitting end to the receiving end using the wireless communication.

Description

[0001] The present invention relates to a method and system for determining transmission power allocation and parameters in a MIMO-OFDM based block AMC environment,

The following embodiments relate to a method and system for determining transmission power allocation and parameters in a MIMO-OFDM based Block AMC environment. And more particularly, to a method and system for determining transmission power allocation and transmission parameters for maximizing data throughput in a wireless communication environment.

The emergence of innovative technologies such as MIMO and OFDM have led to the rapid development of wireless communication technology.

The latest communication technologies such as 802.11n, 802.11ac, LTE and LTE-A are based on the MIMO BIC-OFDM system and can transmit multiple signals at the same time. Therefore, link adaptation The structure and complexity are increased. Research is needed on algorithms that perform adaptive and efficient link adaptation in accordance with continuously developed wireless communication technologies and environments.

Conventionally, the channel state information at the receiver (CSIR) is concentrated on the block AMC (Adaptive Modulation and Coding), and only a brief information is transmitted to the transmitter. For example, there is a transmission parameter. In addition, since dynamic power allocation in a spatial domain is not possible, Singular Value Decomposition (SVD) is required to enable dynamic power distribution.

Embodiments describe transmission power allocation and parameter determination methods and systems in a MIMO-OFDM based block AMC environment, and more particularly, to a method and system for determining transmission power allocation and parameters in a MIMO-OFDM based block AMC environment. More particularly, Power distribution and parameter determination methods and systems.

Embodiments use TCI as a transmission power allocation technique suitable for a block AMC environment and use a signal-to-noise ratio (SNR) that reflects the PER limit using an efficient power allocation scheme and an MCS (Modulation and Coding Scheme) selection algorithm in a block AMC environment. (SNR) threshold is set as a threshold in the TCI technique, and an optimal MCS is selected through a comprehensive calculation. Thus, efficient power distribution is possible, and performance in terms of effective throughput and PER And to provide a method and system for determining transmission power allocation and parameters in an improved MIMO-OFDM based block AMC environment.

In a MIMO-OFDM-based block AMC environment according to an exemplary embodiment, a transmission power allocation and a parameter determination method include estimating a channel state at a receiver through data received from a transmitter through wireless communication; Transmitting the channel information obtained by estimating the channel state at the receiving end to the transmitting end via the wireless communication through feedback; Determining parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment using the channel information at the transmitter; Generating the next transmission data using the parameters at the transmitting end; And transmitting the data from the transmitting end to the receiving end using the wireless communication.

Here, the transmitting end and the receiving end can transmit data in units of packets when the data is transmitted.

The transmitting end and the receiving end are multi-antenna structures and can perform spatial multiplexing to increase a data rate through spatial streams using the multi-antenna structure.

The algorithm is based on MCS selection and power allocation (TDM) that provides a data throughput that reflects the PER limit using Truncated Channel Inversion (TCI) with a high effective SNR (effective SNR) using an SNR threshold power allocation can be performed.

The step of determining parameters through the algorithm may include detecting independent streams in the MIMO channel through Singular Value Decomposition (SVD) at the transmitting end; And distributing the dynamic transmission power for each of the streams at the transmitting end through the SVD.

The determining of the parameters through the algorithm may include determining a combination of a modulation level and a coding rate as a Modulation and Coding Scheme (MCS) according to the channel information at the transmitter, And can be used as the above parameters.

The step of transmitting the data to the receiver using the wireless communication includes dividing a given frequency band into a plurality of independent subcarriers, transmitting a plurality of signals simultaneously, performing channel coding and interleaving, Can be applied in units of bits.

In a MIMO-OFDM-based block AMC environment according to another embodiment, a transmission power allocation and parameter determination system receives channel information, determines parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment, A transmission terminal for generating next transmission data using the transmission data; And a receiver for transmitting channel information obtained by estimating the channel state through the received data to the transmitter using feedback via wireless communication, wherein the transmitter receives the channel information from the receiver, To the receiving end using the wireless communication.

Here, the transmitting end and the receiving end can transmit data in units of packets when the data is transmitted.

The transmitting end and the receiving end are multi-antenna structures and can perform spatial multiplexing to increase a data rate through spatial streams using the multi-antenna structure.

The algorithm is based on MCS selection and power allocation (TDM) that provides a data throughput that reflects the PER limit using Truncated Channel Inversion (TCI) with a high effective SNR (effective SNR) using an SNR threshold power allocation can be performed.

The transmitting end includes a stream detecting unit for detecting independent streams in a MIMO channel through SVD (Singular Value Decomposition); And a transmission power distributing unit for distributing dynamic transmission power for each of the streams.

The transmitter may designate a combination of a modulation level and a coding rate as a modulation and coding scheme (MCS) according to the channel information, and use the parameter as the determined parameters.

The transmitting terminal may divide a given frequency band into a plurality of independent subcarriers, transmit a plurality of signals simultaneously, and apply channel coding and interleaving in units of bits.

Embodiments of the present invention can provide a method and system for determining transmission power allocation and parameters in a MIMO-OFDM-based block AMC environment capable of maximizing data throughput in a wireless communication environment.

According to embodiments, TCI is used as a transmission power allocation scheme suitable for a block AMC environment using an efficient power allocation scheme and an MCS selection algorithm in a block AMC environment, and a SNR threshold value reflecting the PER limit is used in a TCI scheme In the MIMO-OFDM-based block AMC environment where efficient power distribution is possible and performance is improved in terms of goodput and PER by selecting the optimal MCS by a comprehensive calculation by setting the threshold value, transmission power distribution and parameters A determination method and a system can be provided.

1 is a diagram illustrating a process of transmitting and receiving data between a transmitting and a receiving end according to an embodiment of the present invention.
2 is a diagram illustrating a CSIT environment MIMO BIC-OFDM system structure according to an embodiment.
3 is a graph showing the effective SNR according to an embodiment.
4 is a graph illustrating PER for power distribution schemes in accordance with one embodiment.
5 is a graph illustrating BIC-OFDM PER in an AWGN channel according to an embodiment.
6 is a graph illustrating PER of a link adaptation algorithm according to an embodiment.
7 is a graph illustrating the effectiveput of a link adaptation algorithm according to one embodiment.

Hereinafter, embodiments will be described with reference to the accompanying drawings. However, the embodiments described may be modified in various other forms, and the scope of the present invention is not limited by the embodiments described below. In addition, various embodiments are provided to more fully describe the present invention to those skilled in the art. The shape and size of elements in the drawings may be exaggerated for clarity.

Embodiments are directed to a method and system for determining transmission power allocation and transmission parameters for maximizing data throughput in a wireless communication environment based on a Multiple-Input Multiple-Output (MIMO) Bit-Interleaved Coded (BIC) Orthogonal Frequency Division Multiplexing .

It is possible to newly consider Block AMC (Adaptive Modulation and Coding) in the Full Channel State Information at the Transmitter (CSIT) environment in which both the transmitter and the receiver know the channel information. Block AMC in this new transmission environment can perform singular value decomposition (SVD) and gain performance improvement by adjusting transmission power per stream. Accordingly, it is possible to provide a transmission power allocation and transmission parameter selection algorithm suitable for a system environment that performs Full CSIT Block AMC.

This transmission power allocation and transmission parameter selection algorithm will be described in detail below.

Link adaptation is a technique that maximizes communication performance by selecting transmission parameters to effectively correspond to a randomly changing radio channel environment. There are various channel environments depending on the channel model and existence of interference. The transmission parameters include modulation level, coding rate, transmit power, and the like. The communication performance includes data throughput, power efficiency, service quality, quality of service).

Adaptive Modulation and Coding (AMC) is a kind of link adaptation technique. It can select an appropriate modulation level and coding rate according to channel conditions and use it for transmission. In general, a combination of a specific modulation level and a coding rate can be designated as one modulation and coding scheme (MCS) and used as a decision parameter. As an example, MCS has WLAN 802.11n.

Table 1 shows an example of the MCS Table.

In a MIMO-OFDM-based block AMC, in the case of a MIMO-OFDM system, there may be a plurality of symbols in one transmission signal. MIMO can simultaneously transmit a plurality of symbols in a spatial domain, and OFDM can simultaneously transmit a plurality of symbols in a spectral domain.

The Block AMC can apply the MCS determined by the algorithm to the entire transmission signal in the same way.

1 is a diagram illustrating a process of transmitting and receiving data between a transmitting and a receiving end according to an embodiment of the present invention.

Referring to FIG. 1, in a MIMO-OFDM based block AMC environment, a transmission power allocation and parameter determination system may include a transmitter 110 and a receiver 120.

In the MIMO-OFDM based block AMC environment, the transmitting terminal 110 receives channel information, determines parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment, and transmits the determined parameters So that next transmission data can be generated.

In addition, the transmitting terminal 110 receives channel information from the receiving terminal 120, and can transmit the generated data to the receiving terminal 120 using wireless communication.

The transmitting terminal 110 can transmit data in units of packets when transmitting data. The transmitter 110 may have a multiple antenna structure and may perform spatial multiplexing to increase a data rate through spatial streams using a multi-antenna structure.

The algorithm uses a Truncated Channel Inversion (TCI) having a high effective signal to noise ratio (SNR) using a threshold of a signal-to-noise ratio (SNR) A modulation and coding scheme (MCS) that provides reflected data throughput and a link adaptation that can perform power allocation. The details of this will be described below.

The transmitting terminal 110 can distribute the transmission power between streams through Singular Value Decomposition (SVD). More specifically, the transmitting end 110 may include a stream detecting unit and a transmission power dividing unit. The stream detection unit can detect independent streams in the MIMO channel through SVD (Singular Value Decomposition). The transmission power allocation unit may distribute a dynamic transmission power for each stream.

In addition, the transmitter 110 may use a combination of a modulation level and a coding rate as a modulation and coding scheme (MCS) according to the channel information, and use the selected modulation level and coding rate as determined parameters. The transmitter 110 divides a given frequency band into a plurality of independent subcarriers and simultaneously transmits a plurality of signals and applies channel coding and interleaving on a bit basis .

The receiving terminal 120 can transmit the channel information obtained by estimating the channel state through the received data to the transmitting terminal 110 through the wireless communication through the feedback.

Here, the receiving end 120 can transmit data in units of packets when transmitting data. The receiver 120 may have a multiple antenna structure and perform spatial multiplexing in which a data rate is increased through spatial streams using a multi-antenna structure.

In this MIMO-OFDM based block AMC environment, transmission power allocation and parameter determination methods in a MIMO-OFDM based block AMC environment can be explained in detail using a transmission power allocation and parameter determination system.

In a MIMO-OFDM based block AMC environment, a transmission power allocation and a parameter determination method include estimating a channel state in a receiving terminal 120 through data received from a transmitting terminal 110 through wireless communication; Transmitting the channel information obtained by estimating the channel state at the receiving end 120 to the transmitting end 110 through wireless communication through feedback; Determining parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment using channel information at a transmitter 110; Using the parameters at the transmitting end 110 to generate the next transmission data; And transmitting data from the transmitting end 110 to the receiving end 120 using wireless communication.

Here, the transmitting terminal 110 and the receiving terminal 120 can transmit data in units of packets when transmitting data. The transmitter 110 and the receiver 120 may have a multiple antenna structure and may perform spatial multiplexing to increase a data rate through spatial streams using a multiple antenna structure .

And, the above algorithm uses an SNR threshold value to select a MCS selection and a power level that provides a data throughput that reflects the PER limit, using a Truncated Channel Inversion (TCI) having a high effective SNR (effective SNR) And may be link adaptation capable of performing power allocation.

The step of determining the parameters through the algorithm may be to distribute the transmit power between streams via Singular Value Decomposition (SVD) at the transmitter 110. More specifically, the transmitting terminal 110 detects independent streams in a MIMO channel through SVD (Singular Value Decomposition), and transmits a dynamic transmission power / RTI >

In the step of determining parameters through the algorithm, a combination of a modulation level and a coding rate is designated as one MCS (Modulation and Coding Scheme) according to channel information in the transmitter 110, It can be used as parameters.

The step of transmitting data to the receiving end 120 using wireless communication includes dividing a given frequency band into a plurality of independent subcarriers, transmitting a plurality of signals at the same time, performing channel coding and interleaving, Can be applied in units of bits.

Hereinafter, the transmission power allocation and parameter determination system and method in a MIMO-OFDM based block AMC environment will be described in more detail.

First, in the CSIT environment packet-based wireless communication, link adaptation and communication in the CSIT environment can be performed through the following process.

The receiving terminal 120 can estimate the channel state through the received data. The channel information obtained from the receiving end 120 is fed back to the transmitting end 110 through the feedback, and the transmitting end 110 performs link adaptation using the received channel information. That is, it can generate next transmission data with the parameters determined through the algorithm, and transmit the generated data to the receiving end 120.

At this time, data transmission between the transmitting and receiving ends can be performed on a packet basis.

In a MIMO BIC-OFDM based transmission system, MIMO is a structure having N _t transmit antennas and N _r receive antennas. It is possible to perform spatial multiplexing for increasing the overall data rate through a total of N _s = min (N _t , N _r ) spatial streams using a multiple antenna structure.

In the bit-interleaved-coded OFDM (BIC-OFDM), a given frequency band can be divided into N independent subcarriers and multiple signals can be simultaneously transmitted. Channel coding and interleaving can be applied in units of bits.

Here, two assumptions can be made about the channel.

First, it is related to quasi-static, and it can be assumed that the channel does not change until transmission for one packet is completed.

The second is related to frequency-selective, and it can be assumed that a channel value is different for each subcarrier due to a plurality of multipaths.

In the inter-stream transmission power distribution through singular value decomposition (SVD), in the CIST environment, independent streams in the MIMO channel can be detected through SVD.

The SVD for the nth (th) subcarrier MIMO channel can be expressed by the following equation.

는 특이값(singular value)이라 불리며, n번째 부반송파(subcarrier) MIMO 채널 내 존재하는 독립적인 스트림(stream)들의 고유 채널 값으로 볼 수 있다. here,

Is called a singular value and can be regarded as a unique channel value of independent streams existing in an n-th subcarrier MIMO channel.

The transmission power distribution in the transmission terminal 110 can perform dynamic transmission power distribution for each stream using V _n calculated through SVD.

At this time, dynamic transmission power distribution is impossible if the environment is not a CSIT environment.

In the CSIT environment MIMO BIC-OFDM system structure, data transmission between the transmitting and receiving ends 110 and 120 will be described in detail below.

2 is a diagram illustrating a CSIT environment MIMO BIC-OFDM system structure according to an embodiment.

Referring to FIG. 2, in the CSIT environment MIMO BIC-OFDM system structure, data transmission between a transmitter and a receiver can be confirmed.

A transmit bit vector b defined as one packet is subjected to channel coding as much as a coding rate determined by the proposed algorithm and then subjected to an interleaving process, To generate a signaled symbol vector s at a modulation level determined by the algorithm of FIG.

에 제안 알고리즘을 통해 결정된 weight matrix 와 SVD를 통해 얻은 V 매트릭스를 차례로 곱하여 전송 벡터(transmit vector)

를 생성할 수 있다. Then, a stream vector generated through a serial-to-parallel mapper,

The weight matrix determined by the proposed algorithm and the V matrix obtained through the SVD are sequentially multiplied to obtain a transmit vector,

Lt; / RTI >

를 얻을 수 있다. A cyclic prefix is added to a transmit vector generated by applying IFFT to the received signal, a cyclic prefix is removed from a signal received through the channel matrix H, and a receive vector is applied by applying FFT,

Can be obtained.

를 하나의 벡터(vector)로 결합하고, 디인터리빙(deinterleaving)과 디코딩(decoding) 과정을 통해 수신 비트 벡터(receive bit vector)

를 얻을 수 있다. In addition, by applying soft-bit detection to the detected vector by multiplying the detection matrix W,

Are combined into a single vector and a received bit vector is obtained through deinterleaving and decoding.

Can be obtained.

The calculation process between the symbol vector of the n-th subcarrier and the detected vector can be expressed as the following equation.

Hereinafter, the power allocation of the proposed algorithm using the TCI technique will be described in detail.

The proposed algorithm can perform power allocation through link adaptation using Truncated Channel Inversion (TCI). Here, the TCI is a power allocation technique that complements the Channel Inversion (CI) technique. The TCI is a power allocation technique that uses the existing technology (AJ Goldsmith and PP Varaiya, "Capacity of fading channels with channel side information," IEEE Trans. 43, No. 6, pp. 1986-1992, Nov. 1997.) is a power allocation method supplementing the Channel Inversion (CI) technique.

)들은 n번째 부반송파(subcarrier) 내 스트림(stream)들의 채널 이득(channel gain)으로 볼 수 있으며, 각 스트림(stream)에 대한 신호 대 잡음비(Signal to Noise Ratio; SNR)는 다음 식과 같이 정의될 수 있다. The singular value detected through SVD (

) Can be regarded as the channel gain of streams in the nth subcarrier and the signal to noise ratio (SNR) for each stream can be defined as: have.

The CI scheme compares SNRs between streams to distribute power to a relatively good stream and distributes power to a worse stream to distribute power to all streams stream is equal to the effective SNR (effective SNR).

For example, the CI technique can be expressed as:

Such a CI may suffer a large loss in the effective SNR value when the amount of power distributed to the stream is in proportion to 1 / SNR and the state of the stream to be distributed is very bad.

에 대한 문턱값(threshold)을 설정하여 전력 분배(power allocation)이 적용될 스트림(stream) 수를 조절할 수 있다. The TCI technique

The number of streams to which power allocation is to be applied can be adjusted by setting a threshold for the power allocation.

For example, the TCI technique can be expressed as:

Therefore, by using the TCI technique, the effective SNR is increased about twice.

3 is a graph showing the effective SNR according to an embodiment.

Referring to FIG. 3, a graph illustrating the suitability of a TCI-based transmission power distribution in a block AMC environment is shown. The SNR = 0 dB, the streams detected through channel information given instantaneously in a 4x4 antenna environment (Effective SNR) and average value for each subcarrier of the last stream after applying the other power allocation techniques.

Here, the dotted line indicates an effective SNR (effective SNR) per subcarrier, and the solid line indicates an average.

Thus, equal power distribution has the lowest effective SNR, and the TCI scheme using the SNR threshold can have the highest effective SNR (effective SNR).

Table 2 shows the effective SNR (SNR) according to different power distribution schemes per SNR.

4 is a graph illustrating PER for power distribution schemes in accordance with one embodiment.

Referring to FIG. 4, channel inversion, water filling (AJ Goldsmith and PP Varaiya, "Capacity of fading channels with channel side information," IEEE Trans. Info. Theory, vol. 43, No. 6, pp. 1986-1992, Nov. 1997.) and equal power allocation can be used to graph the PER measured by SNR for MCS 0, 4, and 7 .

Therefore, PER performance is best when CI is used, and can be attributed to the effective SNR of the last stream which is relatively high.

Water-filling is an optimized power distribution solution in terms of capacity, but in an environment where the same modulation and coding rates are applied to all transmission symbols, such as Block AMC, Low PER performance.

The TCI transmit power distribution and the optimal MCS can be selected to reflect the error rate limitation. At this time, it is possible to perform MCS selection and power allocation that satisfy the PER condition and provide the highest data throughput.

First, the MCS selection problem can be set as follows.

Here, the number of streams used for each subcarrier may be summed to select the MCS that gives the highest value when multiplied by the data rate. Also, since it is a block AMC environment, it is also possible to calculate only the number of subcarriers to be used.

Then, it is possible to set the number of used streams per subcarrier applying the TCI technique.

대신

을 스트림(stream) 사용 여부를 결정 기준으로 사용할 수 있다. To effectively reflect the PER limit

instead

Can be used as a criterion for determining whether to use a stream.

When using a particular MCS, it is possible to select the maximum number of streams giving an effective SNR that is higher than the SNR threshold reflecting the PER constraint.

)할 수 있다. 더 구체적으로, 전송이 이루어지는 동안에는 부채널(sub-channel)들이 독립적이고 일정한(constant) 채널 값을 가지고 있으므로, 각 채널들을 다양한 SNR을 가진 부가 백색 가우스 잡음(additive white Gaussian noise; AWGN) 채널로 볼 수 있다. Then, the SNR threshold value required to satisfy the PER condition for each MCS is set as a look-up table (

)can do. More specifically, since sub-channels have independent and constant channel values during transmission, each channel may be viewed as an additive white Gaussian noise (AWGN) channel with varying SNRs. .

5 is a graph illustrating BIC-OFDM PER in an AWGN channel according to an embodiment.

Referring to FIG. 5, for example, a graph of a PER of an MCS in a BIC-OFDM system having an AWGN channel is used as a look-up table. The SNR threshold value corresponding to the PER condition (threshold) can be found by MCS.

Through the above graph, the SNR threshold value per MCS satisfying PER = 10% can be expressed as follows.

Table 3 shows the SNR threshold per MCS for PER = 10%.

The power allocation matrix can be constructed as follows using the P value of TCI.

When a specific MCS is used, a power allocation matrix can be configured by using an optimal number of streams for each subcarrier.

이 선택되면,

로 설정할 수 있다. And with the optimal MCS

Is selected,

.

와 전력 분배 매트릭스(power allocation matrix)

를 찾아 전송에 사용할 수 있다.
Therefore, an optimal MCS capable of achieving an algorithm target with given channel information

And a power allocation matrix

And can be used for transmission.

In order to verify the performance of the proposed algorithm, the simulation results will be described in detail below.

The simulation parameters (based on the 802.11n specification) can be expressed as:

As selectable parameters, MCSs in Table 1 can be used and Table 3 can be used as a look-up table.

The proposed algorithm is a link adaptation algorithm based on Truncated Channel inversion (AMC) based on Truncated Channel Inversion (TCI), and can analyze and compare the proposed algorithm and the following existing algorithms.

IEEE VTC-2006 Fall, pp. 1 ", IEEE Trans. Lett., Vol. 10, pp. -5, Sep. 2006.) is a link adaptation algorithm based on the LC (Levin-Campello) algorithm that performs optimal bit-loading within limited transmission power. It operates in the same CSIT environment MIMO BIC-OFDM system as the proposed algorithm, and can be bit-loaded by subcarriers and streams.

(High-throughput low-complexity link adaptation for MIMO BIC-OFDM systems, "IEEE Trans. Commun. Commun. , vol. 59, pp. 1078-1088, Apr. 2011.) is an algorithm that performs link adaptation through block AMC and antenna selection in a MIMO BIC-OFDM environment. Block AMC is applied in the same way as the proposed algorithm, but the on-off power distribution can be performed.

6 is a graph illustrating PER of a link adaptation algorithm according to an embodiment.

Referring to FIG. 6, the gray dotted lines on both sides are a graph of a PER of a combination of 1 stream and MCS 0 and 4 streams and MCS 7 combination, and the bound adaptation of link adaptation performance, Can be set.

All of the three algorithms satisfy the PER limit of 10% except for 0 dB. As the SNR increases, PER performance improves.

Also, PER performance of link adaptation based on GLC algorithm is the best, and PER performance of proposed algorithm is better than that of Block AMC environment.

FIG. 7 is a graph illustrating the goodput of a link adaptation algorithm according to one embodiment.

The following equation can be used to calculate goodput.

Referring to FIG. 7, a link adaptation through a GLC algorithm capable of independent AMC for all streams and subcarriers provides the highest goodput performance, and a block AMC-based The performance of the AMCS link adaptation can provide the lowest effective goodput performance.

The proposed algorithm, like AMCS, is based on Block AMC, but it achieves increased goodput performance by distributing power according to the link adaptation environment.

As the higher SNR approaches the full stream and the highest MCS, the performance of all algorithms converge.

As described above, according to the embodiments, it is possible to propose an efficient power distribution scheme and an MCS selection algorithm in a block AMC environment. Block AMC is a transmission power allocation scheme suitable for TCI, and SNR threshold that reflects PER limit is set as a threshold in TCI technique and optimal MCS selection is performed through comprehensive calculation. The performance can be improved in terms of goodput and PER.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, controller, arithmetic logic unit (ALU), digital signal processor, microcomputer, field programmable array (FPA) A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing apparatus may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (14)

Estimating a channel state at a receiver through data received from a transmitter through wireless communication;
Transmitting the channel information obtained by estimating the channel state at the receiving end to the transmitting end via the wireless communication through feedback;
Determining parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment in which the transmitter and the receiver know the channel information using the channel information;
Generating the next transmission data by equally applying the parameters determined in the transmitting terminal to the transmission signal; And
Transmitting the data from the transmitting end to the receiving end using the wireless communication;
Lt; / RTI >
Wherein determining parameters via the algorithm comprises:
Detecting independent streams in a MIMO channel through a Singular Value Decomposition (SVD) at the transmitting end; And
And distributing dynamic transmission power for each of the streams at the transmitting end via the SVD,
The algorithm comprises:
A modulation level and a coding rate are selected according to the channel state and used for transmission and a combination of a modulation level and a coding rate is converted into a modulation and coding Scheme) and determines the parameter as the parameter. The transmission power is distributed through link adaptation in a block AMC (Adaptive Modulation and Coding) environment using Truncated Channel Inversion (TCI)
The distribution of the transmission power using the TCI (Truncated Channel Inversion)
In order to increase the effective SNR, a threshold value is set in SNR (Signal to Noise Ratio) to control the number of streams applied to power allocation. And allocating power to the MIMO-OFDM based block AMC environment. The method according to claim 1,
The transmitting end and the receiving end,
Transmitting in the form of a packet when transmitting the data
A method for determining transmission power allocation and parameters in a MIMO-OFDM-based block AMC environment. The method according to claim 1,
The transmitting end and the receiving end,
A multi-antenna structure is used to perform spatial multiplexing that increases the data rate through spatial streams using the multi-antenna structure
A method for determining transmission power allocation and parameters in a MIMO-OFDM-based block AMC environment. The method according to claim 1,
The algorithm comprises:
(MCS) that provides a data throughput that reflects the PER limitation using a Truncated Channel Inversion (TCI) with a high effective SNR (effective SNR) using a SNR (Signal to Noise Ratio) threshold. Coding Scheme and link adaptation to perform power allocation.
A method for determining transmission power allocation and parameters in a MIMO-OFDM-based block AMC environment. delete delete The method according to claim 1,
Wherein the step of transmitting the data to the receiving end using the wireless communication comprises:
A frequency band is divided into a plurality of independent subcarriers and a plurality of signals are simultaneously transmitted and channel coding and interleaving are applied in units of bits
A method for determining transmission power allocation and parameters in a MIMO-OFDM-based block AMC environment. A transmitter for receiving channel information, determining parameters through an algorithm in a CSIT (Channel State Information at the Transmitter) environment, and applying the determined parameters to a transmission signal to generate next transmission data; And
A receiver for transmitting channel information obtained by estimating the channel state through the received data to the transmitter using wireless communication through feedback;
/ RTI >
The transmitting end transmits,
A stream detector for detecting independent streams in a MIMO channel through SVD (Singular Value Decomposition); And
And a transmission power distribution unit for distributing dynamic transmission power for each of the streams,
Receiving the channel information from the receiving terminal, transmitting the generated data to the receiving terminal using the wireless communication,
The algorithm comprises:
A modulation level and a coding rate are selected according to the channel state and used for transmission and a combination of a modulation level and a coding rate is converted into a modulation and coding Scheme) and determines the parameter as the parameter. The transmission power is distributed through link adaptation in a block AMC (Adaptive Modulation and Coding) environment using Truncated Channel Inversion (TCI)
The distribution of the transmission power using the TCI (Truncated Channel Inversion)
In order to increase the effective SNR, a threshold value is set in SNR (Signal to Noise Ratio) to control the number of streams applied to power allocation. And a power allocation and power allocation in a MIMO-OFDM based block AMC environment. 9. The method of claim 8,
The transmitting end and the receiving end,
Transmitting in the form of a packet when transmitting the data
A transmission power allocation and parameter determination system in a MIMO-OFDM based block AMC environment. 9. The method of claim 8,
The transmitting end and the receiving end,
A multi-antenna structure is used to perform spatial multiplexing that increases the data rate through spatial streams using the multi-antenna structure
A transmission power allocation and parameter determination system in a MIMO-OFDM based block AMC environment. 9. The method of claim 8,
The algorithm comprises:
(MCS) that provides a data throughput that reflects the PER limitation using a Truncated Channel Inversion (TCI) with a high effective SNR (effective SNR) using a SNR (Signal to Noise Ratio) threshold. Coding Scheme and link adaptation to perform power allocation.
A transmission power allocation and parameter determination system in a MIMO-OFDM based block AMC environment. delete delete 9. The method of claim 8,
The transmitting end transmits,
A frequency band is divided into a plurality of independent subcarriers and a plurality of signals are simultaneously transmitted and channel coding and interleaving are applied in units of bits
A transmission power allocation and parameter determination system in a MIMO-OFDM based block AMC environment.

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